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Re: [PCN] Concensus questions from Thursday's PCN meeting

Steven Blake <steven.blake@ericsson.com> Wed, 19 March 2008 15:19 UTC

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From: Steven Blake <steven.blake@ericsson.com>
To: Georgios Karagiannis <karagian@cs.utwente.nl>
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Date: Wed, 19 Mar 2008 11:16:42 -0400
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Subject: Re: [PCN] Concensus questions from Thursday's PCN meeting
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Georgios,

Let me try to paraphrase the scenario you are describing:

- There is an ingress-egress aggregate whose traffic is split across
  multiple paths via ECMP.
- Traffic is admitted along this split path.
- One (or more) of the paths fails.
- One (or more) of the remaining paths becomes severely congested (for
  example because there is traffic from other ingress-egress aggregates
  flowing along that path).
- Marked packets are preferentially dropped at the severely congested
  router(s).  As a consequence, not enough marked traffic arrives at the
  egress router to drive the CLE for the ingress-egress aggregate above
  the threshold needed to trigger a response (termination, say).

Does this description accurately capture your scenario?


Regards,

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Steven Blake                <steven.blake@ericsson.com>
Ericsson/Redback Networks               +1 919-472-9913

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